xref: /openbmc/u-boot/drivers/rtc/pcf8563.c (revision e77e65df)
1 /*
2  * (C) Copyright 2001
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 /*
9  * Date & Time support for Philips PCF8563 RTC
10  */
11 
12 /* #define	DEBUG	*/
13 
14 #include <common.h>
15 #include <command.h>
16 #include <rtc.h>
17 #include <i2c.h>
18 
19 #if defined(CONFIG_CMD_DATE)
20 
21 static uchar rtc_read  (uchar reg);
22 static void  rtc_write (uchar reg, uchar val);
23 
24 /* ------------------------------------------------------------------------- */
25 
26 int rtc_get (struct rtc_time *tmp)
27 {
28 	int rel = 0;
29 	uchar sec, min, hour, mday, wday, mon_cent, year;
30 
31 	sec	= rtc_read (0x02);
32 	min	= rtc_read (0x03);
33 	hour	= rtc_read (0x04);
34 	mday	= rtc_read (0x05);
35 	wday	= rtc_read (0x06);
36 	mon_cent= rtc_read (0x07);
37 	year	= rtc_read (0x08);
38 
39 	debug ( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
40 		"hr: %02x min: %02x sec: %02x\n",
41 		year, mon_cent, mday, wday,
42 		hour, min, sec );
43 	debug ( "Alarms: wday: %02x day: %02x hour: %02x min: %02x\n",
44 		rtc_read (0x0C),
45 		rtc_read (0x0B),
46 		rtc_read (0x0A),
47 		rtc_read (0x09) );
48 
49 	if (sec & 0x80) {
50 		puts ("### Warning: RTC Low Voltage - date/time not reliable\n");
51 		rel = -1;
52 	}
53 
54 	tmp->tm_sec  = bcd2bin (sec  & 0x7F);
55 	tmp->tm_min  = bcd2bin (min  & 0x7F);
56 	tmp->tm_hour = bcd2bin (hour & 0x3F);
57 	tmp->tm_mday = bcd2bin (mday & 0x3F);
58 	tmp->tm_mon  = bcd2bin (mon_cent & 0x1F);
59 	tmp->tm_year = bcd2bin (year) + ((mon_cent & 0x80) ? 1900 : 2000);
60 	tmp->tm_wday = bcd2bin (wday & 0x07);
61 	tmp->tm_yday = 0;
62 	tmp->tm_isdst= 0;
63 
64 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
65 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
66 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
67 
68 	return rel;
69 }
70 
71 int rtc_set (struct rtc_time *tmp)
72 {
73 	uchar century;
74 
75 	debug ( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
76 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
77 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
78 
79 	rtc_write (0x08, bin2bcd(tmp->tm_year % 100));
80 
81 	century = (tmp->tm_year >= 2000) ? 0 : 0x80;
82 	rtc_write (0x07, bin2bcd(tmp->tm_mon) | century);
83 
84 	rtc_write (0x06, bin2bcd(tmp->tm_wday));
85 	rtc_write (0x05, bin2bcd(tmp->tm_mday));
86 	rtc_write (0x04, bin2bcd(tmp->tm_hour));
87 	rtc_write (0x03, bin2bcd(tmp->tm_min ));
88 	rtc_write (0x02, bin2bcd(tmp->tm_sec ));
89 
90 	return 0;
91 }
92 
93 void rtc_reset (void)
94 {
95 	/* clear all control & status registers */
96 	rtc_write (0x00, 0x00);
97 	rtc_write (0x01, 0x00);
98 	rtc_write (0x0D, 0x00);
99 
100 	/* clear Voltage Low bit */
101 	rtc_write (0x02, rtc_read (0x02) & 0x7F);
102 
103 	/* reset all alarms */
104 	rtc_write (0x09, 0x00);
105 	rtc_write (0x0A, 0x00);
106 	rtc_write (0x0B, 0x00);
107 	rtc_write (0x0C, 0x00);
108 }
109 
110 /* ------------------------------------------------------------------------- */
111 
112 static uchar rtc_read (uchar reg)
113 {
114 	return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR, reg));
115 }
116 
117 static void rtc_write (uchar reg, uchar val)
118 {
119 	i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val);
120 }
121 
122 #endif
123